Adjustable thermostat

Abstract

An adjustable thermostat as disclosed having an adjustment stem journaled for rotation on the thermostat body for adjusting the operating temperature of the thermostat. Mounted on the adjusting stem is a pointer member formed of deformable material such as Nylon and providing a peripheral surface which engages with interference stationary surfaces on the thermostat body. Interengagement is provided between the peripheral surface and the stationary surfaces which causes deformation of the pointer member and creates friction resisting rotation of the pointer and of the adjusting stem. A detent-like structure is provided by flats formed on the peripheral surface of the pointer which mate with the corresponding surfaces of the body to tend to lock the pointer and in turn adjusting stem at a predetermined temperature.

I claim: 
     
       1. A thermostat comprising a substantially rigid body, an adjusting stem journaled on said body for rotation about an axis to adjust the operating temperature of said thermostat, said body providing a fixed surface spaced from said axis, an indicator mounted on said stem for rotation therewith and providing a generally cylindrical radially extending portion formed of deformable material, said deformable material providing a deformable surface engaging said fixed surface and being deformed from its unstressed condition by such engagement, said engagement between said fixed surface and said deformable surface providing friction resisting rotation of said indicator and in turn said stem with respect to said body. 
     
     
       2. A thermostat as set forth in claim 1 wherein the fixed surface on said body is a planar surface and the deformable surface on said indicator is a substantially circular surface. 
     
     
       3. A thermostat as set forth in claim 1 wherein the fixed surface on said body is a planar surface substantially parallel to said axis, and the deformable surface on said indicator is a generally cylindrical surface, and said deformation of said deformable surface is substantially radial with respect to said axis. 
     
     
       4. A thermostat as set forth in claim 3 wherein said deformable surface includes planar portions which mate with said fixed surface of said body to provide detent means. 
     
     
       5. A thermostat as set forth in claim 4 wherein said peripheral surface is provided by a radially extending flange having a width in the direction of said axis less than the width of said indicator in the direction of said axis. 
     
     
       6. A thermostat comprising a substantially rigid body, an adjusting stem journaled on said body for rotation about an axis to adjust the operating temperature of said thermostat, said body providing a pair of projections symmetrically positioned with respect to said axis, an indicator mounted on said stem for rotation therewith and providing a generally cylindrical radially extending flange formed of radially deformable elastic material, said projections providing fixed surfaces spaced from said axis by a distance less than the radius of said flange when the material of said indicator is unstressed, said flange being formed with a pair of flats substantially constituting cords of the cylindrical flange which mate with associated of said fixed surfaces when said indicator stem is in one position, the deformability of said flange allowing rotation of said indicator from said one position for adjusting the operating temperature of said thermostat and producing frictional contact between the said fixed surfaces and deformable surfaces to resist rotation of said indicator stem. 
     
     
       7. A thermostat comprising a body, an adjusting stem journaled in said body, an indicator mounted on said stem for rotation therewith about an axis, rotation of said stem and indicator adjusting the operating temperature of said thermostat, said indicator being formed of deformable plastic material and providing a peripheral surface which is resiliently deformable in a radial direction, said body providing a stationary surface engaging a radially deforming said peripheral surface and producing friction resisting rotation of said indicator and stem with respect to said body. 
     
     
       8. A thermostat as set forth in claim 7 wherein said body provides similar and opposed stationary surfaces each of which engages said peripheral surface and produces friction resisting rotation of said indicator with respect to said body. 
     
     
       9. A thermostat as set forth in claim 5 wherein said peripheral surface includes a pair of flat portions operable to mate with an associated stationary surface and provide detent means tending to maintain said indicator in a predetermined position with respect to said body. 
     
     
       10. A thermostat as set forth in claim 9 wherein said indicator is molded Nylon. 
     
     
       11. A thermostat comprising a body, an adjusting stem journaled in said body, an indicator mounted on said stem for rotation therewith, rotation of said stem and indicator adjusting the operating temperature of said thermostat, said indicator being molded of elastically deformable material and providing a peripheral surface which is resiliently deformable in a radial direction and providing first opposed portions which are inclined in a radial direction, said body providing a stationary surface engaging said peripheral surface and having second surface portions which are inclined in a radial direction and mate with said first portions to resist rotation of said indicator and said stem when said indicator and stem are in a predetermined orientation with respect to said body, rotation of said indicator and stem from said predetermined orientation producing radial deformation of said peripheral surface and friction between said peripheral surface and said stationary surface resisting relative rotation of said indicator with respect to said body.